diff --git a/src/MainTask.h b/src/MainTask.h
index af02b60..8d746e0 100644
--- a/src/MainTask.h
+++ b/src/MainTask.h
@@ -609,7 +609,12 @@ protected:
       if (GPIO_IS_VALID(settings.externalPump.gpio)) {
         configuredGpio = settings.externalPump.gpio;
         pinMode(configuredGpio, OUTPUT);
-        digitalWrite(configuredGpio, LOW);
+        digitalWrite(
+          configuredGpio,
+          settings.externalPump.invertState
+            ? HIGH 
+            : LOW
+        );
 
       } else if (configuredGpio != GPIO_IS_NOT_CONFIGURED) {
         configuredGpio = GPIO_IS_NOT_CONFIGURED;
@@ -637,7 +642,12 @@ protected:
     
     if (!settings.externalPump.use) {
       if (vars.externalPump.state) {
-        digitalWrite(configuredGpio, LOW);
+        digitalWrite(
+          configuredGpio,
+          settings.externalPump.invertState
+            ? HIGH 
+            : LOW
+        );
 
         vars.externalPump.state = false;
         vars.externalPump.lastEnabledTime = millis();
@@ -650,7 +660,12 @@ protected:
 
     if (vars.externalPump.state && !this->heatingEnabled) {
       if (this->extPumpStartReason == MainTask::PumpStartReason::HEATING && millis() - this->heatingDisabledTime > (settings.externalPump.postCirculationTime * 1000u)) {
-        digitalWrite(configuredGpio, LOW);
+        digitalWrite(
+          configuredGpio,
+          settings.externalPump.invertState
+            ? HIGH 
+            : LOW
+        );
 
         vars.externalPump.state = false;
         vars.externalPump.lastEnabledTime = millis();
@@ -658,7 +673,12 @@ protected:
         Log.sinfoln(FPSTR(L_EXTPUMP), F("Disabled: expired post circulation time"));
 
       } else if (this->extPumpStartReason == MainTask::PumpStartReason::ANTISTUCK && millis() - this->externalPumpStartTime >= (settings.externalPump.antiStuckTime * 1000u)) {
-        digitalWrite(configuredGpio, LOW);
+        digitalWrite(
+          configuredGpio,
+          settings.externalPump.invertState
+            ? HIGH 
+            : LOW
+        );
 
         vars.externalPump.state = false;
         vars.externalPump.lastEnabledTime = millis();
@@ -674,7 +694,12 @@ protected:
       this->externalPumpStartTime = millis();
       this->extPumpStartReason = MainTask::PumpStartReason::HEATING;
 
-      digitalWrite(configuredGpio, HIGH);
+      digitalWrite(
+        configuredGpio,
+        settings.externalPump.invertState
+          ? LOW 
+          : HIGH
+      );
 
       Log.sinfoln(FPSTR(L_EXTPUMP), F("Enabled: heating on"));
 
@@ -683,7 +708,12 @@ protected:
       this->externalPumpStartTime = millis();
       this->extPumpStartReason = MainTask::PumpStartReason::ANTISTUCK;
 
-      digitalWrite(configuredGpio, HIGH);
+      digitalWrite(
+        configuredGpio,
+        settings.externalPump.invertState
+          ? LOW 
+          : HIGH
+      );
 
       Log.sinfoln(FPSTR(L_EXTPUMP), F("Enabled: anti stuck"));
     }
diff --git a/src/Settings.h b/src/Settings.h
index 80ab827..ecb4d15 100644
--- a/src/Settings.h
+++ b/src/Settings.h
@@ -162,6 +162,7 @@ struct Settings {
   struct {
     bool use = false;
     uint8_t gpio = DEFAULT_EXT_PUMP_GPIO;
+    bool invertState = false;
     unsigned short postCirculationTime = 600;
     unsigned int antiStuckInterval = 2592000;
     unsigned short antiStuckTime = 300;
diff --git a/src/utils.h b/src/utils.h
index 5824c2f..8442dbf 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -542,6 +542,7 @@ void settingsToJson(const Settings& src, JsonVariant dst, bool safe = false) {
     auto externalPump = dst[FPSTR(S_EXTERNAL_PUMP)].to<JsonObject>();
     externalPump[FPSTR(S_USE)] = src.externalPump.use;
     externalPump[FPSTR(S_GPIO)] = src.externalPump.gpio;
+    externalPump[FPSTR(S_INVERT_STATE)] = src.externalPump.invertState;
     externalPump[FPSTR(S_POST_CIRCULATION_TIME)] = roundf(src.externalPump.postCirculationTime / 60, 0);
     externalPump[FPSTR(S_ANTI_STUCK_INTERVAL)] = roundf(src.externalPump.antiStuckInterval / 86400, 0);
     externalPump[FPSTR(S_ANTI_STUCK_TIME)] = roundf(src.externalPump.antiStuckTime / 60, 0);
@@ -1492,6 +1493,15 @@ bool jsonToSettings(const JsonVariantConst src, Settings& dst, bool safe = false
       }
     }
 
+    if (src[FPSTR(S_EXTERNAL_PUMP)][FPSTR(S_INVERT_STATE)].is<bool>()) {
+      bool value = src[FPSTR(S_EXTERNAL_PUMP)][FPSTR(S_INVERT_STATE)].as<bool>();
+
+      if (value != dst.externalPump.invertState) {
+        dst.externalPump.invertState = value;
+        changed = true;
+      }
+    }
+
     if (!src[FPSTR(S_EXTERNAL_PUMP)][FPSTR(S_POST_CIRCULATION_TIME)].isNull()) {
       unsigned short value = src[FPSTR(S_EXTERNAL_PUMP)][FPSTR(S_POST_CIRCULATION_TIME)].as<unsigned short>();
 
diff --git a/src_data/locales/cn.json b/src_data/locales/cn.json
index abf02f8..10a3a6b 100644
--- a/src_data/locales/cn.json
+++ b/src_data/locales/cn.json
@@ -455,6 +455,7 @@
       "extPump": {
         "use": "使用外置循环泵",
         "gpio": "继电器 GPIO引脚",
+        "invertState": "切换 GPIO 状态",
         "postCirculationTime": "后循环时间 <small>(分钟)</small>",
         "antiStuckInterval": "防卡死间隔时间<small>(天)</small>",
         "antiStuckTime": "防卡死运行时长<small>(分钟)</small>"
diff --git a/src_data/locales/en.json b/src_data/locales/en.json
index c3f880d..24ac153 100644
--- a/src_data/locales/en.json
+++ b/src_data/locales/en.json
@@ -455,6 +455,7 @@
       "extPump": {
         "use": "Use external pump",
         "gpio": "Relay GPIO",
+        "invertState": "Invert GPIO state",
         "postCirculationTime": "Post circulation time <small>(min)</small>",
         "antiStuckInterval": "Anti stuck interval <small>(days)</small>",
         "antiStuckTime": "Anti stuck time <small>(min)</small>"
diff --git a/src_data/locales/it.json b/src_data/locales/it.json
index 454fb8e..2e4f15c 100644
--- a/src_data/locales/it.json
+++ b/src_data/locales/it.json
@@ -455,6 +455,7 @@
       "extPump": {
         "use": "Usa pompa/circolatore esterno",
         "gpio": "GPIO relè",
+        "invertState": "Inverti stato GPIO",
         "postCirculationTime": "Tempo di post circolazione <small>(min)</small>",
         "antiStuckInterval": "Intervallo antiblocco <small>(days)</small>",
         "antiStuckTime": "Tempo antiblocco <small>(min)</small>"
diff --git a/src_data/locales/nl.json b/src_data/locales/nl.json
index 70cacd3..65ff5a3 100644
--- a/src_data/locales/nl.json
+++ b/src_data/locales/nl.json
@@ -417,6 +417,7 @@
       "extPump": {
         "use": "Gebruik externe pomp",
         "gpio": "Relais GPIO",
+        "invertState": "Inverteer GPIO-status",
         "postCirculationTime": "Nacirculatietijd <small>(min)</small>",
         "antiStuckInterval": "Anti-vastloopinterval <small>(dagen)</small>",
         "antiStuckTime": "Anti-vastlooptijd <small>(min)</small>"
diff --git a/src_data/locales/ru.json b/src_data/locales/ru.json
index b712c3c..7a6e627 100644
--- a/src_data/locales/ru.json
+++ b/src_data/locales/ru.json
@@ -455,6 +455,7 @@
       "extPump": {
         "use": "Использовать доп. насос",
         "gpio": "GPIO реле",
+        "invertState": "Инвертировать состояние GPIO",
         "postCirculationTime": "Время постциркуляции <small>(в минутах)</small>",
         "antiStuckInterval": "Интервал защиты от блокировки <small>(в днях)</small>",
         "antiStuckTime": "Время работы насоса <small>(в минутах)</small>"
diff --git a/src_data/pages/settings.html b/src_data/pages/settings.html
index cec0087..f5c4494 100644
--- a/src_data/pages/settings.html
+++ b/src_data/pages/settings.html
@@ -731,6 +731,11 @@
                   <input type="checkbox" name="externalPump[use]" value="true">
                   <span data-i18n>settings.extPump.use</span>
                 </label>
+
+                <label>
+                  <input type="checkbox" name="externalPump[invertState]" value="true">
+                  <span data-i18n>settings.externalPump.invertState</span>
+                </label>
               </fieldset>
 
               <div class="grid">
@@ -928,6 +933,7 @@
           // Extpump
           setCheckboxValue("[name='externalPump[use]']", data.externalPump.use);
           setInputValue("[name='externalPump[gpio]']", data.externalPump.gpio < 255 ? data.externalPump.gpio : '');
+          setCheckboxValue("[name='externalPump[invertState]']", data.externalPump.invertState);
           setInputValue("[name='externalPump[postCirculationTime]']", data.externalPump.postCirculationTime);
           setInputValue("[name='externalPump[antiStuckInterval]']", data.externalPump.antiStuckInterval);
           setInputValue("[name='externalPump[antiStuckTime]']", data.externalPump.antiStuckTime);